This invention relates to protective devices for electrical connectors exposed to high voltages, and more specifically to a multi-electrode device for monitoring and protecting a plurality of electrical connectors.
Prior art protective and monitoring devices for electrical contacts and connectors are known. Such protective devices typically monitor a single contact or connector pair and provide an output discharge signal in response to the presence of an excessive voltage on the protected connector. Bulky transformers are required to isolate any protective or monitoring circuitry from the circuit being monitored.
There is thus a need in the prior art for simplified protective devices providing isolated outputs without requiring the use of bulky transformers.
Multi-electrode over-voltage gaps are known in the prior art, but, similarly to the single connector pair protective devices described above, such multi-electrode devices also require bulky isolation transformers. Accordingly, there is a need in the prior art for multi-electrode protective devices to provide compact monitoring and protection for electrical connectors or contacts independently of any isolation transformers.
Electical circuits also require protection from high voltage pulses having fast rise times. Prior art protective gas discharge devices, however, are incapable of providing stable breakdown voltages for rapidly changing voltages on the monitored circuits. There is accordingly a need in the prior art to provide protective devices for electrical connectors having stabilized voltage breakdown characteristics, both for DC voltage levels and for fast rising voltage pulses.
Spark gap protective devices are frequently encased in organic materials for protection and packaging. Under storage conditions, such organic materials are capable of emitting hydrogen gas. The hydrogen gas can permeate through nickel, copper or nickel-cobalt alloys into the gas filled discharge chamber, thus changing the purity of the fill-gas and its breakdown voltage. There is thus a need in the prior art for protective devices which may be encased in organic materials but which, nonetheless, are not subject to the negative effects of hydrogen permeation.